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Furious Justin Bieber fans today demanded a refund after the star was two hours late on stage - forcing many to leave his show early in tears and others to sleep rough after missing trains home.

Angry parents told how their children - as young as eight - sobbed after they failed to see the full show because they had to leave or face the prospect of being stranded at the O2.

Bieber was meant to take to the stage at 8.30pm after his support acts Jaden Smith, Cody Simpson and Carly Rae Jespen had finished but did not appear until almost two hours later at 10.22pm.

It meant there were was loud booing from the 20,000 audience - some who had been queuing since 6.30pm - as they had to watch an empty stage for more than an hour while the organisers played Michael Jackson songs.

John Lush, 48. an advertising manager, who took his daughter 10-year-old daughter Amelie Lush and her friend Ellie Compton, said they were only able to stay for one song before they had to leave to catch the train home to Bromley, Kent.

He said: “I am absolutely livid. I don’t think a refund would compensate the emotional damage he has done to my children. Giving money to a 10-year-old who couldn’t see their hero is not enough, not when they have school the next day. The girls were so angry and upset at Bieber by time they left.”

Parents who paid as much as £68 a ticket to take their children to see their pop icon branded Bieber’s disregard for his young fans as “disgusting”.

Michelle Christianson, from Oxford, brought her 12-year-old daughter Enya, who was in tears after being forced to leave early to make it home.

She said: “We have seen little kids leaving before the thing even started. It’s just terrible to leave early having spent so much money.”

VIDEO: FANS BOO BIEBER AT GIG

Mother-of-two Karen Reeve, from Southend-on-Sea in Essex waited outside the O2 Arena to collect her daughters for more than two hours.

She said: “I’m absolutely irate. I’m furious. They have GCSEs and I cannot believe Justin Bieber would do something like this.

“There was no explanation, no apology. His fans are children. This is not on.”

The show did not finsh until midnight meaning some youngsters fell asleep while others parents took them home early fearing they would have to miss school today.

Louise Cooper, who had taken her nine-year-old daughter Cerys Cooper-Jones to the show, said fans were in tears outside the venue after they were forced to miss most of the concert in order to get home.

Ms Cooper, a journalist and financial analyst, said: “There were teenage girls crying outside. It’s one thing if your demographic is 50-year-olds, but his demographic is lots of little girls who need to go home and go to bed. I think he is going a bit weird.”

Bieber, who turned 19 last week, was staying tight-lipped today after tweeting to his 35 million followers yesterday about how he was looking forward to the first of his four 02 Gigs. He wrote: “In a good mood. Got my friends and team with me here and ready for Day 1 at the O2. London get ready!”

His management were refusing to comment this morning amid reports of a “crisis meeting” between his record label, representatives and tour operators.

An O2 spokesman said: “The O2 has the safety and welfare of all its customers as a first priority. A number of transport contingency plans were actioned to make sure that all Bieber fans were able to make their way home safely after the concert finished.”

Bieber has been photographed partying in the capital into the early hours almost every night since he arrived in the UK for his tour, ending up in a kebab shop on Edgware Road at 6am on his birthday.

Lloyd Becker, whose wife took their eight-year-old daughter Isabella to the concert, said: “Isabella absolutely hates him now. She’s going to see One Direction next month. I absolutely 100 per cent want a refund.”

Students Steph Costa, 16, and Sian Elder, 17, were forced to sleep rough at the 02 before getting an early train to Bracknell from Waterloo.

Steph said: “We want free tickets for another gig at least. We were not told why Justin was late and now we have to miss college today.”

The O2 apologised via Twitter for the delay.

Their tweet at 10:36pm last night said: “Justin Bieber is now on stage and apologises for the lateness of his show”

At 11:08pm it added: “Sorry to all the Justin Bieber fans for the lateness of his show tonight. The Tube will still be running when the show finishes.”